Lead delivery device and method

ABSTRACT

A medical apparatus includes a guidewire and a fixator catheter. The fixator catheter comprises a tubular body with a distal portion and a proximal portion, and further includes a distal opening, a fixator secured to the distal portion, and a body opening arranged between the fixator and the proximal portion. The guidewire passes through the body opening and the distal opening of the fixator catheter. The fixator is movable between a compact configuration and an expanded configuration and, in the expanded condition, is capable of anchoring the guidewire and fixator catheter in a lumen of a blood vessel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Ser. No. 12/183,401,filed Jul. 31, 2008, which claims the benefit of U.S. ProvisionalApplication No. 61/076,183, filed on Jun. 27, 2008.

This application is a continuation-in-part of U.S. Ser. No. 12/183,105,filed Jul. 31, 2008, which claims the benefit of U.S. ProvisionalApplication No. 61/076,183, filed on Jun. 27, 2008.

This application is related to U.S. Patent Application No. ______ filedconcurrently herewith, entitled “Lead Delivery Device And Method.”

This application is related to U.S. patent application Ser. No.11/468,910 filed on Aug. 31, 2006, which is a division of U.S. patentapplication Ser. No. 10/254,196, filed on Sep. 24, 2002, now U.S. Pat.No. 7,107,105.

The disclosures of the above applications are incorporated herein byreference.

INTRODUCTION

Various cardiac devices providing electrical stimulation, rhythmmanagement, or resynchronization therapy to the heart includeimplantable electrically conductive leads in contact with excitableheart or other body tissue.

The present teachings provide a device and method for delivering animplantable electrically conductive lead to a target site for a use witha cardiac device.

SUMMARY

The present teachings provide a medical apparatus that includes animplantable electrically conductive lead for a cardiac device, the leadhaving an internal bore terminating at a distal lead opening, and a leaddelivery device for delivering the distal end of the lead to a bloodvessel during implantation of the lead. The lead delivery deviceincludes a removably anchorable guidewire, and a fixator attached to adistal portion of the guidewire for anchoring the guidewire. The fixatoris movable between a compact configuration and an expandedconfiguration. The fixator is capable of passing through the distal leadopening of the lead in the compact configuration. The fixator is capableof exerting a holding force in the range of about 0.89 to 4.45 N in thelumen of the blood vessel in the expanded configuration.

The present teachings also provide a medical method that includesinserting a distal end of cannulated catheter through cardiac tissueinto a main cardiac vessel, attaching an expandable fixator to a distalportion of a guidewire, inserting the guidewire through the catheter,advancing the guidewire past the distal end of the catheter and into atarget site in a lumen of a branching vessel, expanding the fixator intothe target site, removably anchoring the fixator into the lumen with aholding force in the range of about 0.89 to 4.45 N, and removing thecatheter. The method further includes advancing an implantableelectrically conductive lead of a cardiac device over the guidewire tothe target site without moving the guidewire while tensioning theguidewire, and delivering the distal portion of the lead at the targetsite.

In another aspect, the present teachings provide a medical apparatusthat includes a cardiac device for providing cardiac therapy, or cardiacsensing, or a combination thereof, an implantable electricallyconductive lead having proximal and distal ends, the proximal endcouplable to the cardiac device, the lead having an internal boreterminating at a distal opening at the distal end, and a lead deliverydevice for delivering the distal end of the lead to a blood vesselduring implantation of the lead. The lead delivery device includes aremovably anchorable guidewire, and a fixator attached to a distalportion of the guidewire, the fixator movable between a compactconfiguration and an expanded configuration. The fixator has a compactwidth less or equal to about 0.483 mm and is capable of passing throughthe distal lead opening of the lead in the compact configuration. Thefixator has an expanded width up to about 5 mm, and is capable ofexerting a holding force in the range of about 0.89 to 4.45 N in thelumen of the blood vessel in the expanded configuration.

In a further aspect, the present teachings provide a medical apparatuscomprising a guidewire and a fixator catheter. The fixator cathetercomprises a tubular body with a distal portion and a proximal portion.The fixator catheter further comprises a distal opening, a fixatorsecured to the distal portion, and a body opening arranged between thefixator and the proximal portion. The guidewire is passed through thebody opening and the distal opening of the fixator catheter. The fixatoris movable between a compact configuration and an expandedconfiguration.

In yet another aspect, the present teachings provide a medical methodcomprising passing a guidewire through a fixator catheter. The fixatorcatheter comprises a tubular body with a distal portion and a proximalportion. The fixator catheter further comprises a distal opening, afixator secured to the distal portion, and a body opening arrangedbetween the fixator and the proximal portion. The guidewire is passedthrough the body opening and the distal opening of the fixator catheter.The method further comprises navigating the guidewire and fixatorcatheter to a desired site. At the desired site, the fixator is expandedto an expanded configuration in order to releasably secure the fixatorcatheter. An implantable electrically conductive lead of a cardiacdevice is advanced over the guidewire to the desired site while thefixator is deployed.

Further areas of applicability of the present teachings will becomeapparent from the description provided hereinafter. It should beunderstood that the description and specific examples are intended forpurposes of illustration only and are not intended to limit the scope ofthe present teachings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present teachings will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is an environmental view of a lead delivery device according tovarious embodiments of the present teachings;

FIG. 1A is an environmental view of the lead delivery device of FIG. 1,shown in a second aspect;

FIG. 1B is an enlarged detail of the lead delivery device of FIG. 1B;

FIG. 2 is a perspective environmental view of the cardiac device withthe lead implanted after the lead delivery device of FIG. 1B is removed;

FIG. 3 is a plan view of a lead delivery device having a fixatoraccording to the present teachings, the lead delivery device shown withthe fixator in an expanded configuration;

FIG. 4 is a plan view of a lead delivery device having a fixatoraccording to the present teachings, the lead delivery device shown withthe fixator in a compact configuration;

FIGS. 5-11 illustrate various fixators for a lead delivery deviceaccording to the present teachings;

FIG. 11A is a top view of the fixator of FIG. 11;

FIG. 12 is a side view of the fixator of FIG. 11, illustrating adeployment mechanism;

FIG. 13 is a sectional view of a lead delivery device according to thepresent teachings with a fixator in a compact configuration inside alead;

FIG. 14 is the lead delivery device of FIG. 13, shown with the fixatorin an expanded configuration outside the lead;

FIG. 15 is the lead delivery device of FIG. 13, shown with the fixatorpartially retracted inside the lead;

FIG. 16 is an end view of a distal end of an electrical lead with anoffset distal opening;

FIG. 17 is a plan view of a lead delivery device having a fixatoraccording to the present teachings, the lead delivery device shown withthe fixator in a compact configuration;

FIG. 18 is a plan view of a lead delivery device having a fixatoraccording to the present teachings, the lead delivery device shown withthe fixator in an expanded configuration;

FIG. 19 is an environmental view of a lead delivery device according tovarious embodiments of the present teachings;

FIG. 20 is an environmental view of a lead delivery device according tovarious embodiments of the present teachings;

FIG. 21 is an environmental view of a lead delivery device according tovarious embodiments of the present teachings;

FIG. 22 is an environmental view of a lead delivery device according tovarious embodiments of the present teachings;

FIG. 23 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 24 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 25 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 26 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 27 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 28 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 29 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 30 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 31 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 32 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 33 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 34 illustrates an exemplary fixator for a lead delivery deviceaccording to the present teachings;

FIG. 35 illustrates an exemplary device for expanding a fixator for alead delivery device according to the present teachings;

FIG. 36 illustrates an exemplary device for expanding a fixator for alead delivery device according to the present teachings;

FIG. 37 illustrates an exemplary device for expanding a fixator for alead delivery device according to the present teachings;

FIG. 38 illustrates an exemplary device for expanding a fixator for alead delivery device according to the present teachings; and

FIG. 39 illustrates an exemplary device for expanding a fixator for alead delivery device according to the present teachings.

DESCRIPTION OF VARIOUS ASPECTS

The following description is merely exemplary in nature and is in no wayintended to limit the present teachings, applications, or uses. Thepresent teachings are applicable to any devices that requireimplantation of electrically conductive leads, including pacemakers,defibrillators or other cardiac devices providing rhythm management,resynchronization therapy or other cardiac therapy.

During left heart (LH) lead delivery methods for implanting cardiactherapy devices, cannulated catheters can be used to provide support andstiffness and allow trackability of the lead into the coronary sinus andmore acute branching vessels. For example, in Cardiac ResynchronizationTherapy (CRT), a special third lead is implanted via the Coronary Sinus(CS) and positioned in a sub-selected cardiac vein to sense and/or pacethe left ventricle in combination with atrial-synchronized,biventricular pacing using standard pacing technology. Following asensed atrial contraction or atrial-paced event, both ventricles arestimulated to synchronize their contraction. The resulting ventricularresynchronization reduces mitral regurgitation and optimizes leftventricular filling, thereby improving cardiac function.

Guidewires can be used inside the Coronary Sinus and Great Cardiac Veinto gain access to acute side branches. A guidewire is placed into thetargeted vessel and the lead is placed over the guidewire and throughthe catheter. Under existing methods, during lead delivery, acompressive force is maintained by a forward pressure on both theguidewire and lead to allow the lead to travel distally in the branchingveins at the target site. The lead itself is designed to providestiffness and steerability characteristics for the purpose of placementinto the vessels. After the LH lead has reached its desired location,the delivery catheters used during the procedure must be removed byslitting because the proximal end of the lead is larger in diameter thanthe bore of the catheter and the catheter cannot be removed over thelead. The slitting procedure requires a very specific skill set,provides multiple avenues for user error and places constraints oncatheter design, construction and use.

In contrast to the existing method described above, the presentteachings provide a lead delivery device method that does not requireslitting the catheter. The lead delivery device includes a guidewirethat can be temporarily anchored in a sub-selected acute coronary veinbranch during lead delivery. Fixation can be provided by a fixator thatexpands from a compact configuration of very low profile fitting insidea lead to an expanded configuration having a dimension large enough toallow sufficient tension to be placed on the guidewire to enable leaddelivery over the guidewire in a zip-line or rope-climbing manner, asdescribed below. The guidewire with the fixator in the compactconfiguration can be guided through the catheter to the target site. Thecatheter can then be removed before the lead is advanced over theguidewire. After the lead is implanted, the fixator is returned to thecompact configuration and removed together with the guidewire throughthe implanted lead without slitting.

An exemplary lead delivery device 100 according to the present teachingsis illustrated during lead delivery of an electrically conductive lead200 in FIGS. 1, 1A and 1B. An implanted lead 200 is shown in FIG. 2,after the lead delivery device 100 is removed. The lead 200 can becannulated having an internal bore or lumen 204, a proximal portion 201,and a distal portion 202. The proximal portion 201 can be coupled with aconnector pin 207 to a connector block of a cardiac device 290, withwhich the lead 200 is in electrical communication. A catheter 250 havinga proximal end 252 and a distal end 254 can be used to insert the leaddelivery device initially through heart tissue 80, as shown in FIG. 1.

The lead delivery device 100 can include a guidewire 102 entering aproximal end 252 of the catheter 250 and exiting through a distal end254 of the catheter 250 as shown in FIG. 1. The guidewire 102 can besolid or cannulated with a bore 103, as shown in FIG. 12. The guidewire102 can include a distal portion 104 terminating in a tip 106. Thedistal portion 104 can be flexible for ease in guiding the guidewire 102through tortuous blood vessels to a target site 82, such as a branchingvein branching off the coronary sinus or other main blood vessel. Thelead delivery device 100 can include a fixator 150 coupled to theguidewire 102. The fixator 150 can assume an expanded or deployedconfiguration for anchoring the guidewire 102 near a target site 82during lead delivery and implantation, as shown in FIGS. 3, and 5-11,illustrating various fixator aspects. Referring to FIG. 1, the catheter250 can be removed by retracting the catheter 250 from heart tissue 80after the lead delivery device is anchored at the target site 82. Noslitting of the catheter 250 is required for removal of the catheter250. After the catheter 250 is removed, the lead 200 can be guided overthe guidewire 102 to the target site 82, as discussed further below.

The fixator 150 can be returned to a compact or undeployedconfiguration, such as the configuration illustrated in FIG. 4, forretracting and removing the guidewire 102 after lead delivery andimplantation. The maximum dimension, diameter or width of the fixator150 in the expanded configuration is denoted as L1 and in the contractedconfiguration as L2, as illustrated in FIGS. 3 and 4 for a fixator inthe form of a balloon.

FIGS. 5-11 illustrate various fixators 150 in their expandedconfiguration showing the maximum dimension L1 for each fixator 150. Thedimension L1 is selected to achieve a fixation force within a bloodvessel of an amount that allows the guidewire 102 to be pulled intension without being dislodged from the blood vessel while the lead ispushed over the guidewire 102, as discussed below. The fixation force Fcan be equal to or greater than about 2.24 N, or about 0.5 lbs, forachieving sufficient fixation within the blood vessel wall. The fixationforce F can generally be in the range of about 0.89 to 4.45 N (or 0.2 to1.0 lbs), depending on various factors, including the geometry of thebranching vessel. The deployed width or dimension L1 corresponding tothis fixation force F can be 5 mm, while the undeployed width ordimension L2 can be maintained to equal to or less than about 0.019inches, or about 0.483 mm, to allow easy passage through commerciallyavailable leads, such as those used with medical devices available fromMedtronic, Inc., of Minneapolis, Minn.

Referring to FIGS. 13-15, the distal portion 202 of an electrical lead200 is illustrated in connection with a guidewire 102 having a width L4and a fixator 150 having an undeployed width L2. The lead 200 isconductive and can deliver therapy in the form of electric energy at thetarget site 82. In one aspect, the lead 200 can also sense and relayinformation about electrical activity from the heart tissue 80 or targetsite 82 back to the cardiac device 290. The lead 200 can have aninternal bore or lumen 204, an internal coil or other conductive element210 and a tip portion 206 that can be an electrode tip with or without aseal. The tip portion 206 can define a distal opening 205 with width L3.In one aspect, the tip portion 206 can include a seal with flexibleflaps, not shown. The guidewire width L4 can be about 0.346 mm (or about0.014 inches) for providing steerability, stiffness and sufficientsupport for lead delivery over the guidewire 102.

The compact width L2 of the fixator 150 can be equal to or less than thewidth L3 of the distal opening 205, such that the fixator 150 can bepushed through the distal opening 205 in the direction C, as shown inFIG. 13. In one aspect the distal opening 205 can be offset relative toa central longitudinal axis of the lead 200, as shown in FIG. 16. Thefixator 150 can be deployed to the expanded configuration within theblood vessel 90 such that the expanded width L1 of the fixator 150 canpress against the internal lumen 92 of the blood vessel 90 with aholding force F, as discussed above, for temporarily anchoring theguidewire 102 into the blood vessel 90, as shown in FIG. 14.

Various fixators 150 can be used to temporarily and removably anchor theguidewire 102 in the lumen 92 of a blood vessel 90. Referring to FIGS. 3and 4, the fixator 150 can be a balloon having first and second ends111, 113 attached to the guidewire 102. The balloon can be inflated, forexample, with a gas or fluid, including a gel or other liquid, providedby a syringe through a valve 110 at a proximal end of the guidewire 102.In another aspect, a luer lock inflation port 120 can be coupled to theguidewire 102 for deploying the balloon. The balloon can be made from apolyblend material which is heated and stretched, placed around theguidewire 102 and bonded at first and second ends 111, 113 of theballoon onto the guidewire 102 with small amounts of cyanoacrylateadhesive, for example. A radio-opaque marker 108 in the form of a bandcan be placed adjacent the second (proximal) end 113 of the balloon forvisualization during guided navigation. The radio-opaque marker 108 canalso be in the form of a radio-opaque balloon coating or radio-opaquefluid filling the balloon. In another aspect, the balloon-type fixator150 can include an etched fixation surface with etched surface fixationformations 154 in the form of bumps, rings, etc., as illustrated inFIGS. 5 and 7. In another aspect, the fixator 150 can be a balloon withspiral or helical or otherwise curved configuration for maintaining apercentage of blood flow through the blood vessel 90 and aiding fixationin tortuous anatomy.

Referring to FIGS. 9-12, the fixator 150 can also be in the form of amechanical anchor with deployable straight wings 160, as shown in FIG.9, or curved wings 160, as shown in FIG. 10, or a pinwheel-type fixator150, as shown in FIGS. 11 and 11A. The mechanical anchor 150 can bedeployed with a longitudinal actuator 170 in the form of a wire orstring or other elongated member passing through the bore 103 of acannulated guidewire 102. Referring to FIG. 12, for example, the anchorwings 160 can pivot about a pivot pin 124 connected to the actuator 170and can be deployed to the expanded position in the direction of arrowsE by pulling the actuator 170 in the direction of arrow D. In otheraspects, the fixator 150 can be in the form of a superelastic wire, suchas nitinol, and can be pre-shaped to expand to an anchorableconfiguration within the blood vessel 90.

In another aspect, fixators 150 including polymer lobes or superelasticor memory-shape wire can be used. Further, the dimensions of the fixator150, including the expanded width L1 and the compact width L2 can beselected to match the range of most common vessel sizes. The expandedshape of the fixator 150 can be selected to increase the contact areawith the blood vessel and or provide multiple contact surfaces forincreasing holding force and stability, as shown in FIGS. 6, 8, and 10,for example. The expanded shape can have a symmetric profile, as shownin FIG. 9, for example, or a non-symmetric profile, as shown in FIG. 6,for example. In other aspects, the expanded shape can have an asymmetricprofile for anchoring unidirectionally rather than bi-directionally.

Further exemplary fixators 150 are illustrated in FIGS. 23-34. Thefixator 150 can be in the form of a mechanical helix that temporarilysecures the guidewire 102 to a vessel wall, as shown in FIG. 23. Themechanical helix may be formed of a metal or polymer material attachedto the distal portion 106 of the guidewire 102. The mechanical helix maybe permanently attached to the distal end 104 of the guidewire 102, ormay selectively retract within, or extend from, an inner lumen of theguidewire 102. The mechanical helix may share a common axis with theguidewire 102 as shown. Alternatively, the axis of the mechanical helixmay be movable to be angled (for example, approximately 90°) withrespect to the axis of the guidewire.

As illustrated in FIG. 24, a balloon fixator 150 may be utilized with alead 200 that does not include an inner lumen. The lumenless lead 200may be guided along the guidewire 102 by guiding passage 208 or similarconnection that slidably couples lead 200 with guidewire 102.Additionally, as discussed more fully below, fixator 150 may take theform of a balloon attached to a fixator catheter 304 through which theguidewire 102 passes.

Fixator 150 may take the form of a magnetic fixator that temporarilysecures the guidewire 102 to a vessel wall, as shown in FIG. 26. Themagnetic fixator 150 will respond to an external magnetic field ormagnetic field outside of the patient that secures the guidewire 102against a vessel wall. Upon removal of the magnetic field, the magneticfixator 150 may be freely moved within the vessel. FIG. 27 illustratesyet another exemplary fixator 150 that comprises at least one expandablelobe 152. The expandable lobe 152 may have various shapes and be made ofa polymer, metal or similar material. The lobe 152 may be deployed tosecure fixator 150 and guidewire 102 within a vessel, and then collapsedor otherwise released from vessel wall for removal.

FIG. 28 illustrates an exemplary fixator 150 that takes the form of aguidewire 102 with an inner lumen terminating in a suction tip throughwhich a suction force may be exerted. The suction force may be appliedto secure the fixator 150 to a vessel wall and, upon removal of thesuction force, the guidewire 102 will be released from attachment to thevessel wall. Alternatively, an adhesive may be used as the fixator 150for securing the guidewire 102 to a vessel wall, as shown in FIG. 29.The adhesive may be a biocompatible adhesive, a bio-gel, or other formof self-dissolving adhesive that temporarily secures the guidewire 102to a vessel wall during a surgical procedure. The adhesive may provide aretention force that permits navigation of the lead 200 during aprocedure, but that allows for removal of the guidewire 102 uponexertion of a force on the guidewire 102 in excess of that expectedduring guidance of the lead 200. In this manner, guidewire 102 may beremoved from vessel after completion of the procedure.

The fixator 150 may also take the form of a temperature controllableportion of the guidewire 102 that may be temporarily adhered to a vesselwall through heating or freezing, as illustrated in FIG. 30. In thisexample, the guidewire 102 may include an inner lumen that may be filledwith a liquid at a temperature that will cause freezing of thetemperature controllable portion of the guidewire 102, which will adhereto the vessel wall. Alternatively, the temperature controllable portionof the guidewire 102 may be heated, e.g., by electrical energy, to causeadhesion between the vessel wall and guidewire 102. Upon removal of theheating or freezing source, the fixator 150 will release from the vesselwall.

FIG. 31 illustrates yet another form of fixator 150. In this example,fixator 150 takes the form of an expandable mesh cage or stent that maybe selectively expanded and contracted. Additionally, the mesh cage orstent may be made of a dissolvable material and released from attachmentwith guidewire 102 after completion of a procedure. In variousembodiments, a permanent mesh cage or stent may be attached to theguidewire 102 by means of a dissolvable material such that the mesh cageor stent is released from attachment with guidewire 102 after completionof a procedure to remain in the blood vessel. Alternatively, the fixator150 may take the form of a portion of the guidewire 102 that may beselectively formed into an expanded shape, as shown in FIG. 32. As shownin FIG. 32, a portion of the guidewire 102 at the distal end 104 may beactivated to form an anchor shape, such as a corkscrew as shown. Theanchor shape of the guidewire 102 may be activated electrically,mechanically or a combination of both. For example, electricallyactivated polymers, metals or other materials may be used to form thefixator 150 such that, when an electric current is provided thereto, thefixator 150 takes an expanded form. Other fixator 150 activation methodsare described more fully below.

Referring now to FIGS. 33-34, a propelled guidewire 102 with apropulsion element that acts as a fixator 150 may be utilized. Thepropulsion force exerted by the guidewire 102 in the forward directionwill counter the force exerted by an operating physician in the backwarddirection when guiding the lead 200 into the target area. In thisexample, the fixator 150 may take the form of propulsion jets (as shownin FIG. 33), a propeller (as shown in FIG. 34) or other propulsionsource.

As discussed above, deployment of the fixator 150 and anchoring canoccur after the cannulation of the coronary sinus CS with the catheter250 and after sub-selection of a side branch with the guidewire 102.Further, fixation of the guidewire 102 by the expandable fixator 150 canbe maintained during lead delivery and terminated after the lead 200 isdelivered to the target vessel at the target site 82. At the discretionof the operating physician, fixation and release can occur multipletimes during the medical procedure. Damage to the lead 200 duringfixation can be avoided because fixator expansion and fixation occursoutside the lead 200.

Various devices and methods of deploying the fixator 150 may beutilized. An example of such a fixator deployment device is shown inFIG. 35, with which the inner lumen of guidewire 102 (or fixatorcatheter 304 discussed more fully below) may be twisted closed throughthe use of removable handles or torque tools 180 and 182. In thismanner, for example, a balloon or other receptacle may be filled withpressurized fluid to enter and maintain the expanded condition.Alternatively, a collapsible sleeve 184 may be secured on the guidewire102 to close the inner lumen, as shown in FIG. 36. The collapsiblesleeve 184 and guidewire 102 may be isodiametric, i.e., having the sameouter diameter. Additionally, an adhesive or high viscosity paste or gel186 may be inserted into and seal the inner lumen, as seen in FIG. 37.Other methods of sealing the inner lumen of the guidewire 102 includeutilizing a clamp or other crimping device to close and seal the innerlumen to maintain the fixator 150 in the expanded condition. In variousembodiments, as FIG. 38 illustrates, a push rod or piston 188 may beslidably engaged with the inner lumen and used to actuate the fixator150 between the expanded and collapsed state. In each of the aboveexamples, each of the deployment systems may be made to be isodiametricwith the guidewire 102 such that they may be deployed through the distalopening 205 of the lead 200.

In other embodiments, as shown in FIG. 39, for example, the proximateend 105 of guidewire 102 may be formed of a self-sealing polymer orsimilar material such that a needle 190 may be inserted into the innerlumen of the guidewire 102 to introduce a pressurized fluid into theinner lumen to expand the fixator 150. After expansion of the fixator150, the needle 190 may be removed from the guidewire 102 and theproximate end 105 will automatically seal the inner lumen, thusmaintaining the pressure within the inner lumen and the fixator 150 inthe expanded condition. As discussed more fully below, a fixatorcatheter 304 may be utilized similarly to the guidewire 102 in the aboveexamples. Furthermore, in each of the above examples, the guidewire 102or fixator catheter 304 may be cut between the closed portion of theinner lumen and the fixator 150 to release the pressure and collapse thefixator 150.

It should be appreciated, that according to the present teachings thelead delivery device 100 with either a balloon or mechanical fixator 150is configured and designed to function as a wedge or anchoring devicefor temporarily anchoring the guidewire 102 during the implantation ofthe electrical lead 200.

Referring to FIGS. 1-2, and 13-15, the cannulated catheter 250 can beinserted through heart tissue 80 into a coronary sinus CS, cardiac greatvein or other main vessel stopping short of a target site 82 that islocated in a sub-selected acute branching vessel 90. The guidewire 102with the fixator 150 in the undeployed compact configuration can beinserted through the catheter 250, advanced past the distal end 254 ofthe catheter 250 through a main vessel to the target site 82 in thebranching vessel 90, as shown in FIG. 1. The fixator 150 can then bedeployed and become anchored in the lumen 92 of the branching vessel 90with a holding force F, as discussed above. The catheter 250 can then beretracted and completely removed with no slitting procedure. The lead200 can be guided over the anchored guidewire 102 until the distalportion 202 of the lead 200 reaches the target site 82, as shown in FIG.1B. The lead 200 can be advanced by keeping the guidewire 102 in tensionwhile pushing the lead 200 in the direction of the fixator 150. When thedistal portion 202 of the lead 200 reaches the target site 82, thefixator 150 can be returned to its undeployed compact configuration andbe retracted through the lumen 204 of the lead 200, as shown in FIG. 15.The lead 200 can remain installed in the target site 82, as shown inFIG. 2, or advanced more distally in the branching vessel 90 beyond theoriginal target site 82 after the removal of the guidewire 102.

It will be appreciated that, in other aspects, the catheter 250 may beretained during the entire lead delivery procedure, such that the leadis inserted through the catheter 250 and over the guidewire 102, but insuch cases slitting of the catheter 250 may not be avoided after leadimplantation. In further aspects, the guidewire 102 and the lead 200 canbe inserted through the catheter 250 in any order, i.e., guidewire 102first, or lead 200 first or at the same time. In all aspects, however,the guidewire 102 can first be advanced to the target site 82 of abranching vessel 90 and the fixator 150 be deployed at the target site82. Only then the distal portion 202 of the lead 200 is advanced to thetarget site 82 by pushing the lead 200 over the guidewire 102 toward thetarget site 82, while the guidewire 102 remains fixed. Specifically, thelead 200 can be advanced to the target site 82 in a climbing-like or zipline-like manner by pulling and tensioning the guidewire 102 while theguidewire 102 remains anchored with the deployed fixator 150 at thetarget site 82.

Referring now to FIG. 17, a lead delivery device 300 according to someembodiments of the present disclosure is illustrated. Lead deliverydevice 300 comprises a guidewire 302 and fixator catheter 304. Guidewire302 may comprise a solid wire (as illustrated) or be cannulated, andincludes proximal portion 344 and distal portion 342. The fixatorcatheter 304 is a cannulated catheter comprising a tubular body 310 witha distal portion 320 and proximal portion 340. A fixator 312 is securedon the distal end 320 of fixator catheter 304. In FIGS. 17-22, fixator312 comprises an inflatable balloon, although any other form of fixatormay be utilized, as described above.

Guidewire 302 passes through fixator catheter 304 such that theguidewire 302 is encased within the tubular body 310 in at least aportion of the distal portion 320 of the fixator catheter 304. In theillustrated embodiments, this is accomplished by passing the distalportion 342 of the guidewire 302 through the body opening 316 of fixatorcatheter 304 such that it extends through the distal opening 314. Inthis manner, the guidewire 302 and fixator catheter 304 are incommunication at their distal portions 342, 320, while being separate attheir proximal portions 344, 340.

Referring now to FIG. 18, lead delivery device 300 is shown in thecondition where fixator 312 is expanded. In the illustration, fixator312 comprises an inflatable balloon that may be expanded by a gas orfluid, as described more fully above. In some embodiments, the tubularbody 310 of the fixator catheter 304 includes a lumen (not shown) thatis in communication with the inflatable balloon 312 and proximal end340. By providing a pressurized gas or fluid to the balloon 312, thefixator 312 is expanded to the expanded configuration. In the expandedconfiguration, the pressure inside balloon 312 will exert a force on acompressible or collapsible portion 313 of tubular body 310. In theillustrated embodiment, the compressible portion 313 is a portion of thelumen of the fixator catheter within the inflatable balloon, however,the compressible portion 313 may comprise a lumen of the balloon itselfor other arrangement. The force exerted by inflatable balloon 312 onportion 313 of tubular body 310 will cause that portion 313 to compressguidewire 302 such that guidewire 302 is secured to fixator catheter304. Portion 313 may be formed by providing a thinner wall in portion313 than is utilized in the remainder of tubular body 310.Alternatively, portion 313 may be formed of a different material thanthat used to form the rest of tubular body 310, or any other alternativestructure may be utilized (such as, adding a constrictive device orother securing mechanism). While the illustration in FIG. 18 shows aninflatable balloon 312 and a compressible or contract portion 313 oftubular body 310 to secure the guidewire 302 to fixator catheter 304,alternative structures and fixators may be substituted such that theguidewire 302 and fixator catheter 304 are secured together in theexpanded configuration, while remaining independently movable in thecompact configuration.

As alluded to above, the guidewire 302 may be secured to the fixatorcatheter 304 by an apparatus other than the collapsible portion 313 oftubular body 310. For example, if the mechanical helix fixator 150illustrated in FIG. 23 is utilized, the fixator catheter 304 may beforced to kink or otherwise secure the guidewire 302 during deploymentand attachment of the mechanical helix to the vessel wall. With themagnetic fixator 150 embodiment illustrated in FIG. 26, an externalmagnetic force may act on a portion of the fixator catheter 304 tosecure the guidewire 302 thereto. With the fixators 150 illustrated inFIGS. 27, 31 and 32, for example, the force utilized to expand thefixator 150 may be utilized to compress and anchor the guidewire 302within the fixator catheter 304, similarly to that described above withrespect to the balloon fixator catheter. A fixator catheter 304 with thesuction tip fixator 150 as illustrated in FIG. 28 may include anadditional suction port for securing the guidewire 302 within thefixator catheter 304. While each of the alternative securing mechanismsdescribed above are associated with particular fixator 150 embodiments,any combination of fixator 150 and securing mechanisms 150 are withinthe scope of the present disclosure.

Referring now to FIGS. 19-22, a method for using lead delivery device300 to implant an implantable electrically conductive lead 360 within ablood vessel 350 is illustrated. Similar to FIG. 1, FIGS. 19-20 show thelead delivery device 300 utilized to implant implantable electricallyconductive lead 360 within the coronary sinus CS of heart tissue 80. Adelivery catheter 250 having a proximal end 252 and distal end 254 maybe utilized to assist in the delivery of guidewire 302 and fixatorcatheter 304 to a target or desired site 82. The fixator catheter 304,with guidewire 302 passed therein, is inserted through catheter 250 andnavigated to a position within the desired site 82. Upon delivery todesired site 82, fixator catheter 304 deploys its fixator 312 to secureguidewire 302 and fixator catheter 304 within blood vessel 350. In theexpanded configuration, fixator 312 exerts a force, as described above,upon the wall of blood vessel 350 sufficient to anchor both theguidewire 302 and fixator catheter 304 in the desired site 82 whiledelivery catheter 250 is removed and/or implantable electricallyconductive lead 360 is delivered to desired site 82, e.g., via guidewire302.

In the illustrations of FIGS. 19 and 20, delivery catheter 250 is shownas being present within the heart tissue 80 during delivery of lead 360.As shown in FIG. 19, in the expanded configuration fixator 312compresses or collapses portion 313 of fixator catheter 304 such thatguidewire 302 is fixedly secured within fixator catheter 304, asdescribed more fully above. Alternatively, as shown in FIG. 20,guidewire 302 may be removed from fixator catheter 304 before fixator312 is expanded. Fixator 312 may then be expanded to fixedly secureguidewire 302 between fixator 312 and the wall of blood vessel 350. Onceguidewire 302 is fixedly secured within blood vessel 350, implantableelectrically conductive lead 360 may be delivered to desired site 82 by,e.g., traveling over guidewire 302. With the guidewire 302 secured, therisk of the lead 360 being delivered incorrectly, i.e., outside ofdesired site 82, due to unintentional movement of guidewire 302 isreduced.

Once lead 360 is delivered to the desired site 82, the fixator 312 maybe contracted to a compact configuration (as shown in FIG. 17, forexample) and both guidewire 302 and fixator catheter 304 may be removedfrom desired site 82 and heart tissue 80. In some embodiments, fixator312 may be utilized to secure lead 360 against blood vessel wall 350while guidewire 302 is removed (see, e.g., FIG. 22). In this manner, itcan be ensured that there is no unanticipated movement of lead 360 fromdesired site 82 while guidewire 302 is removed from the patient's body.

Referring now to FIGS. 21 and 22, a method of finely adjusting theposition of guidewire 302 and lead 360 is illustrated. FIG. 21 showsfixator 312 in the expanded condition wherein guidewire 302 is securedbetween fixator 312 and the wall of blood vessel 350. This isaccomplished, for example, by delivering lead delivery device 300 to thedesired site 82 and then removing guidewire 302 from distal opening 314and body opening 316 of fixator catheter 304. The guidewire 302 may bepulled out of communication with fixator catheter 304 by pushing onfixator catheter 304 until the distal portion 342 of guidewire 302 ispulled out of and exits body opening 316. Then, guidewire 302 may bepushed past the distal portion 320 of fixator catheter 304, asillustrated. Fixator 312 may be expanded to secure guidewire 302 againstthe wall of blood vessel 350 and implantable electrically conductivelead 360 can then be navigated to desired site 82 by, for example,traveling over guidewire 302 through opening 364.

The position of implantable electrically conductive lead 360 andguidewire 302 may be finely adjusted with the selective use of fixatorcatheter 304. Fixator 312 may be expanded to secure guidewire 302 (asshown in FIG. 21) such that the position of lead 360 may be adjusted.Alternatively, as shown in FIG. 22, fixator catheter 304 may be movedsuch that fixator 312 is immediately adjacent the body of lead 360.Fixator 312 may then be expanded to secure lead 360 within blood vessel350. With lead 360 secured, the position of guidewire 302 may beadjusted without the possibility of moving lead 360. In this manner, auser may alternate between securing the guidewire 302 or lead 360 at acertain position, while adjusting unsecured lead 360 or guidewire 302,respectively, and thus more accurately and simply adjust the positioningof lead 360 within desired site 82.

The foregoing discussion discloses and describes merely exemplaryarrangements of the present teachings. Furthermore, the mixing andmatching of features, elements and/or functions between variousembodiments is expressly contemplated herein, so that one of ordinaryskill in the art would appreciate from this disclosure that features,elements and/or functions of one embodiment may be incorporated intoanother embodiment as appropriate, unless described otherwise above.Moreover, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. One skilled in the art will readily recognizefrom such discussion, and from the accompanying drawings and claims,that various changes, modifications and variations can be made thereinwithout departing from the spirit and scope of the present teachings asdefined in the following claims.

1. A medical apparatus, comprising: a guidewire; and a fixator catheter comprising a tubular body with a distal portion and a proximal portion, the fixator catheter further comprising: a distal opening; a fixator secured to the distal portion; and a body opening arranged between the fixator and the proximal portion, wherein the guidewire passes through the body opening and the distal opening of the fixator catheter.
 2. The medical apparatus of claim 1, wherein the fixator comprises a mechanical helix.
 3. The medical apparatus of claim 1, wherein the fixator comprises a magnetic fixator.
 4. The medical apparatus of claim 1, wherein the fixator comprises a at least one expandable lobe.
 5. The medical apparatus of claim 1, wherein the fixator comprises a suction tip.
 6. The medical apparatus of claim 1, wherein the fixator comprises an adhesive.
 7. The medical apparatus of claim 6, wherein the adhesive comprises at least one of a biocompatible adhesive, a bio-gel, a self-dissolving adhesive, and a combination thereof.
 8. The medical apparatus of claim 1, wherein the fixator comprises a temperature controllable portion of the fixator catheter.
 9. The medical apparatus of claim 1, wherein the fixator comprises a stent.
 10. The medical apparatus of claim 1, wherein the fixator comprises a selectively activated portion of the fixator catheter movable between a compact configuration and an expanded configuration.
 11. The medical apparatus of claim 1, wherein the fixator comprises a propulsion element.
 12. The medical apparatus of claim 11, wherein the propulsion element comprises at least one propulsion jet.
 13. The medical apparatus of claim 11, wherein the propulsion element comprises a propeller.
 14. A method for delivering a medical apparatus, comprising: passing a guidewire through a body opening and a distal opening of a fixator catheter, the fixator catheter comprising a tubular body with a distal portion and a proximal portion, a fixator secured to the distal portion and a body opening arranged between the fixator and the proximal portion, navigating the guidewire to a desired site; navigating the fixator catheter to the desired site; releasably securing the fixator proximate the desired site; and advancing an implantable electrically conductive lead of a cardiac device over the guidewire to the desired site while the fixator is secured.
 15. The method of claim 14, wherein the fixator comprises a mechanical helix.
 16. The method of claim 14, wherein the fixator comprises a magnetic fixator.
 17. The method of claim 14, wherein the fixator comprises at least one expandable lobe.
 18. The method of claim 14, wherein the fixator comprises a suction tip.
 19. The method of claim 14, wherein the fixator comprises an adhesive.
 20. The method of claim 19, wherein the adhesive comprises at least one of a biocompatible adhesive, a bio-gel, a self-dissolving adhesive, and a combination thereof.
 21. The method of claim 14, wherein the fixator comprises a temperature controllable portion of the fixator catheter.
 22. The method of claim 14, wherein the fixator comprises a stent.
 23. The method of claim 14, wherein the fixator comprises a selectively activated portion of the fixator catheter movable between a compact configuration and an expanded configuration.
 24. The method of claim 14, wherein the fixator comprises a propulsion element.
 25. The method of claim 24, wherein the propulsion element comprises at least one propulsion jet.
 26. The method of claim 24, wherein the propulsion element comprises a propeller.
 27. The method of claim 14, further comprising: inserting a distal end of a cannulated catheter through cardiac tissue into a main cardiac vessel; inserting the guidewire and fixator catheter through the catheter; advancing the guidewire and fixator catheter past the distal end of the catheter and into the desired site; and removing the catheter; wherein removing the catheter comprises removing the catheter without slitting the catheter.
 28. The method of claim 14, further comprising: inserting a distal end of a cannulated catheter through cardiac tissue into a main cardiac vessel; inserting the guidewire and fixator catheter through the catheter; advancing the guidewire and fixator catheter past the distal end of the catheter and into the desired site; and removing the catheter; wherein removing the catheter comprises removing the catheter prior to advancing the lead to the target site over the guidewire. 